Interessant:Raw meat diet reduces urinary oxalate and calcium excretion rate in dogs.J.C. Dijckera, E.A. Hagen-Plantingaa, H. Evertsa, G. Boschb, I.P. Kemac, W.H. Hendriksa,b.a Division of Nutrition, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL,Utrecht, The Netherlandsb Animal Nutrition Group, Wageningen University, PO Box 338, 6700 AH Wageningen, TheNetherlandsc Department of Laboratory Medicine, University Medical Center, University of Groningen, PO Box30.001, 9700 RB, Groningen, The NetherlandsIntroductionIn dogs, one of the most common stone detected in the urinary tract is composed of calcium oxalate.Two pivotal conditions in calcium oxalate urolithiasis are an increased urinary oxalate and calciumexcretion (Dijcker, 2011).This cohort study evaluated the range of urinary oxalate and calcium excretion within the dogpopulation not suffering from urolithiasis in the Netherlands and identified dietary- and animal-relatedfactors associated with these urine parameters. A second study was performed to determine the effectof a commercial raw meat vs. dry food on urinary oxalate and calcium excretion in a crossover designin dogs.Material & MethodsSpot urine samples were collected from 141 privately-owned dogs. Information regarding dietary- andanimal-related factors and health status was collected through a questionnaire. Data analyses toidentify dietary- and animal-related factors associated with changes in oxalate:creatinine (Ox:Cr) orcalcium:creatinine (Ca:Cr) in the urine were performed by ANOVA using multivariate linearregression analysis (excluding the independent variables with type III SS of P > 0.05).In the second study, spot urine samples were collected from 23 privately-owned dogs fed a dry andraw meat diet in cross-over design in a 4-week period in random order.ResultsUrine Ox:Cr ranged from 21.1 to 170.6 mmol oxalate/mol creatinine and urine Ca:Cr ranged from 3.4to 462.8 mmol/mol. For both urine parameters, increased excretion was associated with dry foodintake, <1 snack/day and breed, whereas increased urine Ox:Cr was associated to male dogs as well.In the second study, feeding the dry food resulted in higher urine Ox:Cr (P<0.001) and Ca:Cr(P<0.022) excretions in dogs.DiscussionThe range of urine Ox:Cr and Ca:Cr of dogs observed in the present study was broad and was coveringmost of the values reported before in experimental studies. In the dogs of the cohort study, intake ofdry diet, compared to raw meat diet, was found to be associated with higher urine Ox:Cr and Ca:Cr.This finding was substantiated in crossover study, where dogs were fed a commercial raw meat anddry diet. The use of spot urine sampling, i.e. the use of urine Ox:Cr and Ca:Cr, is known not to be asaccurate as quantitative urine sampling. Therefore, additional studies with quantitative urinecollections are recommended to test the association with the identified factors of this study.ReferencesDijcker J.C., Plantinga E.A., Van Baal J. & Hendriks W.H. (2011) Influence of nutrition on felinecalcium oxalate urolithiasis with emphasis on endogenous oxalate synthesis. Nutrition ResearchReviews 24, 96-110-12-NRC (2006) Nutrient requirements of dogs and cats. National Research Council (NRC). 1st edn., TheNational Academies Press, Washington